Certain imidazo-isoquinoline compounds are disclosed in U.S. Pat. No. 3,917,610 issued Nov. 4, 1975; they are reported to have certain cardiovascular activities. One such compound is further reported on in Borchard, Fox, and Greeff, "The Positive Inotropic, Antiarrhythmic and Na.sup.+, K.sup.+ -ATPase Inhibitory Effects of the Isoquinoline Derivative, BIIA", Achives of Pharmacology, vol. 312 (1980), pp. 187-192.